The invention relates to ophthalmic mountings of the type useful in eyeglass assemblies, and in particular relates to assemblies of such type wherein a pair of lenses are removably receivable within lens mounting rims of the eyeglass frame.
In presently known opthalmic mounting arrangements, the mounting frame includes a pair of hollow lens mounting rims separated by a solid bridge area on which a nosepiece may be selectively mounted. Typically, one frame material in such designs is a flexible plastic, which permits each of the isolated mounting rims to "give" to facilitate insertion and removal of the replaceable lenses.
In an illustrative embodiment of this type disclosed in U.S. Pat. No. 1,659,l65, each lens is carried in an annular rim or liner provided with a camming wedge on its exterior surface to cooperate with a mating recess in the receiving surface of the frame mounting rim.
Such prior art designs obviously rely on the necessity of natural elasticity of the mating interlocking parts, i.e., the annular lens liner and the peripheral edge of the frame mounting rim. Such natural elasticity is augmented, in the structure of the above-mentioned patent, by the cam pressure of a wedge. In such designs, therefore, it is necessary to make the frame out of flexible materials. Moreover, the use of machined projections and recesses on both the lens liner and the frame make the ophthalmic mounting difficult and expensive to manufacture.